The present invention relates to an electric switch apparatus for sequentially operating a clutch in an automobile power transmission.
In an automobile having an automotive power train using a manually shiftable transmission and a foot-operated clutch unit interposed between the transmission and the output shaft of the automobile engine, gear shifts are effected by manipulating a gearshift lever mounted on the steering column or the floorboard. In general, before the gearshift lever is to be moved to make a gear shift in the transmission, the driver of the automobile is required to depress a clutch pedal to uncouple the clutch unit which has been transmitting the engine drive to the power input shaft of the transmission. The gear-shift lever is thus manipulated by the driver when the clutch unit is in uncoupled position interrupting the transmission of the engine drive to the power input shaft of the transmission. The clutch unit so uncoupled is coupled after the gear shift has been completed, to allow the engine drive to be transmitted to the power input shaft of the transmission.
With the automotive power train of the type described above, the manipulation of the gearshift lever requires skills for the driver to have and is time-consuming and laborious. In view of this, as an improved version effective to overcome these drawbacks and requiring less manufacturing cost than that of the known automotive power train using an automatic transmission and an automatically operated clutch unit, there is known an automotive power train using a manually shiftable transmission and an automatically operated clutch unit such as disclosed in, for example, U.S. Pat. No. 2,732,447, No. 3,910,388, No. 4,144,424 and No. 4,158,404.